I did it a couple of yrs ago at Bumps & Jumps with an L3. I used the IRS lowered extended pod plates and IRS lowered lower A arms. For tires I used 4 purples (pan car style of cource) and grooved them just like dirt foams. I ran a wing mounted on the rear window and used more left rear weight then normal. OH a pan car on dirt with 4 cells feels waaaaaaaaaaay fast with a 19 turn in it.
Like Porksalot said "if it's very smooth" and B & J is quite smooth. After about 5 or so laps Chris ( B & J's owner) just had to try it and did about 5 to 10 laps. I would love to see a class of pan cars with late mod bodies running on the dirt. Specially since I have a car that could be dedicated to dirt

The bad part is my pan ran better than my terminator on the same day.